Implement ConstraintNotSatisfiedError for getusermedia

content/renderer/pepper/pepper_media_stream_video_track_host.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_PEPPER_PEPPER_MEDIA_STREAM_VIDEO_TRACK_HOST_H_
 #define CONTENT_RENDERER_PEPPER_PEPPER_MEDIA_STREAM_VIDEO_TRACK_HOST_H_
 
 #include "base/compiler_specific.h"
 #include "base/memory/weak_ptr.h"
 #include "content/public/renderer/media_stream_video_sink.h"
@@ skipping 67 matching lines @@
   virtual int32_t OnResourceMessageReceived(
       const IPC::Message& msg,
       ppapi::host::HostMessageContext* context) OVERRIDE;
 
   // Message handlers:
   int32_t OnHostMsgConfigure(
       ppapi::host::HostMessageContext* context,
       const ppapi::MediaStreamVideoTrackShared::Attributes& attributes);
 
   void InitBlinkTrack();
-  void OnTrackStarted(MediaStreamSource* source, bool success);
+  void OnTrackStarted(MediaStreamSource* source,
+                      content::MediaStreamRequestResult result,

[yzshen1, 2014/07/25 17:48:49]

content:: is not needed.

+                      const blink::WebString& result_name = blink::WebString());

[yzshen1, 2014/07/25 17:48:49]

Do you really need this default value?
In general default value is not recommended.

[jiajia.qin, 2014/07/28 05:10:20]

In the spec, it says if it is the ConstraintNotSatisfiedError, we need to set
the constraintName that caused the error. But for other error type, it doesn't
say. So here I use a default value. If the result is
CONSTRAINT_NOT_SATISFIED_ERROR, I will transfer the result_name(constraint_name)
too. Otherwise, I only transfer the result and use the default value.

[yzshen1, 2014/07/28 17:37:18]

Could we pass an empty string in the cases that we don't need it, instead of
using a default value?

 
   blink::WebMediaStreamTrack track_;
 
   // True if it has been added to |blink::WebMediaStreamTrack| as a sink.
   bool connected_;
 
   // Number of buffers.
   int32_t number_of_buffers_;
 
   // Size of frames which are received from MediaStreamVideoSink.
@@ skipping 22 matching lines @@
   scoped_refptr<FrameDeliverer> frame_deliverer_;
 
   base::WeakPtrFactory<PepperMediaStreamVideoTrackHost> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PepperMediaStreamVideoTrackHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_MEDIA_STREAM_VIDEO_TRACK_HOST_H_